In U.S. Pat. No. 4,195,275 of Mar. 25, 1980 entitled "A multiple electromagnetic relay", there is described a multiple electromagnetic relay which includes a plurality of individual relays disposed on a base. Each individual relay mainly comprises a stand, a magnetic circuit constituted by a pole piece and a winding, and a moving spring-carrying armature which co-operates with the pole piece.
Proper operation of the individual relay depends in particular on the value of the air gap between the pole piece and the armature.
Up till now, said air gap is obtained as a result of stacking the component parts such as the stand, the pole piece, the armature, the armature stop and the spring carrier.
The air gap tolerance is a function of the sum of the tolerances allowed for the dimensions of the abovementioned parts. To obtain an air gap of acceptable size, care must be taken when adjusting the size of said parts. This increases the cost of the relay. If, in contrast, relatively large variations in the value of the air gap are tolerated, allowance must be made for an increase in the value of the relay control current.
One aim of the invention is to define a method of assembling a relay in such a way as to guarantee a particular size of air gap of the relay without requiring an increase in production accuracy of its component parts.